In the field of vehicle drivetrain components, a transfer case is an apparatus that distributes driving power to more than one driven axle of the vehicle. A typical transfer case receives driving power from the transmission of the vehicle and transfers that power to a primary output shaft that is driven constantly. Transfer of the power through the transfer case often utilizes various gear, and chain and sprocket systems. Transfer cases are often sealed closed during their assembly, ideally to remain sealed throughout the life of the transfer case
Many of the components in a transfer case require lubrication. This lubrication is often sealed within the transfer case in the initial assembly. However, the lubrication within the transfer case can become contaminated over time as the various mechanical components within the transfer case wear against each other. This contamination often includes small bits of metal, and other materials such as ceramics and oxides, which can cause increased wear of the mechanical components, as compared to lubricant with less contaminant. Accordingly, an apparatus for reducing contaminants within a sealed housing enclosing lubricated mechanical components is desired.